Device for drawing off equal thread lengths from two feed spools



Jan. 30, 1962 w LENK DEVICE FOR DRAWI [NG OFF EQUAL THREAD LENGTHS FROM TWO FEED SPOOLS Fi] .ed Dec. 16, 1959 FIGI 0 3| INVENTOR.

\A /LLHELM LENK h g a W +6 ATT'YS nited States Patent fifice filbhi- Patented Jan. 39, 1952 3,018,604 DEVICE FOR DRAWlNG (EFF EQUAL THREAD LENGTHS FROM TWQ FEED SPOULS Wilhelm Lenk, Remscheid-Lennep, Germany, assignor to Banner Maschinenfabrik Aktiengesellschaft, Wuppertal-Oberbarmen, Germany Filed Dec. 16, 1959, Ser. No. 859,943 Claims priority, application Germany Dec. 24, 1958 Claims. (Cl. 574-5852.)

This invention relates to an apparatus or device for drawing off equal thread lengths from a pair of bobbins or feed spools which rotate independently on the same axis. In particular, the invention provides an improve ment in the textile apparatus known as a double twist twisting machine, sometimes referred to as a multiple twister a two for-one twisting machine.

Where two threads are to be twisted on a double twist twisting machine, the common practice has been to draw the threads from a single bobbin or feed spool and feed them into the twisting device. In this process, it is essential that the threads first be wound upon the single feed spool with as equal and uniform a tension as possible. This preliminary step is both time consuming and difficult to achieve, especially in the commercial handling of a large volume of thread.

In order to avoid the preliminary operating step, it was thought that it might be possible to employ two feed spools of the so-called discus or solar type from which the threads would be drawn olf individually and then brought together prior to twisting. However, in the development of this invention, it was found that this procedure is unsatisfactory because one of the thread wound spools or bobbins frequently runs ahead of or behind the other such that unequal thread lengths are unwound. After twisting, there is an undesirable formation of slack threads and ribby or knotted yarn.

One object of the present invention is to provide a satisfactory and improved device for drawing off equal lengths of thread from two bobbins, thereby also avoiding the problems of a single feed spool.

Another object of the invention is to provide a double twist twisting machine capable of handling a large volume of thread in commercial applications.

Yet another object of the invention is to obtain a uniformly twisted thread product free of knots, slack threads and the like.

These and other objects and advantages, of the invention are more clearly illustrated by the following detailed description taken together with the accompanying drawings in which:

FIG. 1. is a side elevational and partially schematic View of a double twist twisting machine constructed in accordance with the improvement of the present invention;

FIG. 2 is a top View of the same;

FIG. 3 is an enlarged view of one portion of the apparatus, illustrating a preferred embodiment of the inven tion; and

FIG. 4 is an enlarged view of another portion of the apparatus illustrating a suitable swivel joint.

it has now beenrf ound in accordance with the invention that equal lengths of thread can be drawn from two separate bobbins by employing apparatus which includes a spindle upon which two bobbins can be independently mounted for rotationon the same axis, a stationary frame or support adjacent to the spindle and bobbins, roller means connected totheframe or support, and means to resiliently urgethe roller means for rotation tangentially against an outer circumferential surface of each of the bobbins, thereby synchronizing the speeds at which the threads are drawn from each bobbin.

The roller means of the apparatus essentially include a unitary or single acting, cylindrical roller which is positioned during operation of the apparatus to rest against the outer thread surfaces of the bobbins and in rolling contact therewith, the axis of the roller being approximately parallel to the axis of the bobbins. The roller is preferably mounted for rotation between the oppositely disposed arms of a yoke which in turn is connected to the stationary frame for reciprocating movement in a plane approximately perpendicularly to the axis of the bobbins. In other words, the roller and its supporting yoke can swing toward or turn away from the spindle and bobbins, but are normally urged inwardly for rolling contact against the bobbins by a spring or the like with sufficient force to provide constant contact with the thread surface.

It is preferred that the oppositely disposed arms carrying the roller be pivotally mounted by means of a common shaft of the yoke such that the roller can pivot slightly inwardly against either bobbin, for example with bobbins having a difference in their diameters. The roller is then mounted in the manner of a universal joint, being spring urged in one direction towards the spindle and bobbins, and its axis or rotating shaft being pivotable about its center point. A good frictional contact with the thread surfaces of both bobbins is thereby assured.

The term bobbin is employed herein to describe a thread wound spool, i.e. both the spool and its thread pack-age which is unwound or drawn off in the usual fashion during the thread twisting operation. The term thread herein is employed to include various fiber forms including yarns, strings, tows, filament bundles and the like. The fibers may be natural or synthetic and the thread may be composed of continuous filaments or staple fibers.

With reference to the drawings, FIG. 1 discloses a double twist twisting machine, partlyin schematic form and with certain conventional portions omitted. In this machine, a stationary frame is provided by spool carrier 1 and various elements connected thereto. The spool carrier 1 is maintained in a stationary position in a conventional manner, e.g. by means of an eccentric weight located on one side of the carrier while inclining the machine from the vertical position shown. A stationary spool carrier can also be achieved by mounting one or more magnets around the carrier at a sufficient distance therefrom to permit passage of the ballooning thread; These magnets are placed opposite other magnets in or on the spool carrier itself, and the attraction between opposing magnets holds the carrier in place. Since these methods of holding the carrier stationary have become quite standard in the art, the drawings have been simplified to avoid showing the corresponding elcmentsof the apparatus.

A hollow spindle 2 extends above the spool carrier 1 and carries rotatably thereon two separate hollow spoolreceiving holders 3 and 4, which fit tightly into the two bobbin spools 5 and 6 which carry thread packages 7 and 8. The bobbins are wound such that the spools must rotate as the thread is drawn therefrom. A stable basket frame is completed by the upper ring 13 connected to spool carrier 1 by side supports such as the cross members 33 and 34.

Outside the circumference of the thread wound bobbins 7 and 8, a turnable shaft or tube 11 is seated at either end, for example by prong 9 to the carrier 1 and by prong 10 to the upper ring 13. The tube 11 has attached thereto, at right angles and about midway between its ends, a swinging arm or yoke handle 12, which is preferably constructed with a swivel or pivot joint 35 as shown in FIG. 4 so that it will freely rotate or pivot on its own axis at its free end. The free end is shaped in the form of a U-shaped or V-shaped or Y-shaped yoke with two oppositely opposed arms 14 and 15 between which is rotatably mounted a friction roller 16. Bobbin engaging surfaces are provided on the enlarged cylindrical ends 17 and 18 of the roller which may rotate around the center axle as shown in FIG. 1 or whichmay be integral with the center axle as shown in FIG. 3.

The tube 11 is pretensioned by means of a torsion spring 19 and is caused to rotate with arm 12, thereby urging the roller surfaces 17 and 18 inwardly against the two corresponding bobbins 7 and 8 along a circumferential surface thereof. The pivot linkage or joint 35 in arm 12 assures that both ends of the roller will press against the bobbins.

During operation, the threads 20 and 21 are drawn off laterally from each bobbin 7 and 8 and conducted through quide eyelets or hooks 22 and 23 on cross member 33. The threads are then conducted in common to a third guide eyelet 24 on the upper ring 13 and around the end of the bobbins over the guide roller 25 and into the hollow bore 26 of the spindle 2. The threads are then drawn through the bore 26 and outwardly through a rotating annular channel or slot (not shown) and to the thread reserve disc 27, all in the conventional manner of a double twist twisting machine. The thread as it emerges from the reserve disc 27 is led outwardly in a rotating balloon 28 around the end of the bobbins, through eyelet 29, over a preliminary draw-oh roll 30 and onto a take-up reel or draw-off rolls 31 and 32, these rolls representing the point at which drawing or unwinding of the threads from the bobbins originates.

The roller 16 and especially the outer contacting surfaces 17 and 18 are most conveniently made of a synthetic resin, such as nylon, in order to avoid thread damage. Greater frictional contact is obtained if the surfaces 17 and 18 are grooved, indented, ribbed or otherwise given an uneven surface contour as shown in FIG. 3.

The design of the roller 16 with means to urge it inwardly against the bobbins causes the running surfaces 17 and 18 to lie or rest with equal pressure on the circumference formed by the thread packages 7 and 8. This rolling frictional contact exercises either a braking effect or an acceleration of the drawing-off velocity of the threads so that one bobbin neither runs ahead of nor falls behind the other bobbin. In other words, if one bobbin begins to deliver more thread by increasing its speed of rotation over the other bobbin, the friction roll tends to brake the first bobbin while also accelerating the second bobbin. In this manner, equal thread lengths are drawn off, even if there is a difference in the outer diameter of the two bobbins.

While the apparatus of the present invention is particularly suitable in the operation of a double twist twisting machine, it can also be employed in any operation where the essential problem is to draw equal and uniform thread lengths from two unwinding bobbins rotating independently on the same axis. This axis may be in a vertical position or in any inclined position down to and including the horizontal.

It is quite difficult to obtain two bobbins which have an identical lateral winding such that equal thread lengths under equal tension can be unwound therefrom. The present invention substantially completely obviates this difficulty, and also avoids the necessity of a preliminary Winding of two threads on the same spool. In double twist twisting machines, the present invention is especially useful because it provides a much simplified and more economical operation.

The invention is hereby claimed as follows:

1. Apparatus for drawing equal lengths of thread from a pair of bobbins independently rotating on the same axis which comprises: a spindle upon which said bobbins are rotatably mounted; a stationary frame adjacent to said spindle and bobbins; roller means connected to said frame and including for each bobbin a substantially cyclindrical roller; means to resiliently urge each of said cyclindrical rollers for rotation tangentially against an outer circumferential surface of its respective bobbin; and means interconnecting said cylindrical rollers independently of said bobbins for synchronization of their rate of revolution.

2. Apparatus for drawing equal lengths of thread from a pair of bobbins independently rotating on the same axis which comprises: a spindle upon which said bobbins are rotatably mounted; a stationary frame adjacent to said spindle and bobbins; roller means including a yoke with two oppositely disposed arms, said yoke being connected to said frame for reciprocating movement in a plane approximately perpendicularly to the axis of said bobbins, and also including a single substantially cylindrical roller rotatably mounted between said oppositely disposed arms on a common axle and extending transversely of both bobbins; and means to resiliently urge said yoke and roller for rotation of the roller tangentially against an outer circumferential surface of each of said bobbins.

3. Apparatus as claimed in claim 2, wherein said oppositely disposed arms carrying said roller are pivotally mounted by means of a common shaft of said yoke.

4. In a double twist twisting machine, the improvement which comprises: a hollow spindle; means to receive two bobbins in a position adjacent each other for independent rotation of said bobbins around the axis of said spindle; guide means to lead a thread outwardly from each bobbin as said thread unwinds therefrom, and to further lead each thread around one end of said bobbins, through said hollow spindle, and then outwardly in a rotating balloon around the other end of said bobbins whereby a twist is imparted to said threads, said guide means including a common guide member where said threads are joined prior to twisting; a stationary frame including means to support said bobbins; roller means connected to said frame; and means to resiliently urge said roller means for rotation tangentially against an outer circumferential surface of each of said bobbins.

5. In a double twist twisting machine, the improvement which comprises: a hollow spindle; means to receive two bobbins in a position adjacent each other for independent rotation of said bobbins around the axis of said spindle; guide means to lead a thread outwardly from each bobbin as said thread unwinds therefrom, and to further lead each thread around one end of said bobbins, through said hollow spindle, and then outwardly in a rotating balloon around the other end of said bobbins whereby a twist is imparted to said threads, said guide means including a common guide member where said threads are joined prior to twisting; a stationary frame including means to support said bobbins; roller means connected to said frame and including a substantially cylindrical roller for each bobbin; means to resiliently urge each of said cylindrical rollers for rotation tangentially against an outer circumferential surface of its respective bobbin; and means interconnecting said cylindrical rollers independently of said bobbins for synchronization of their rate of revolution.

References Cited in the file of this patent UNITED STATES PATENTS 117,644 Kimball Aug. 1, 1871 1,605,276 Peterson Nov. 2, 1926 2,504,020 Hanson Apr. 11, 1950 2,596,428 OMalley May 13, 1952 2,718,363 Roberts Sept. 20, 1955 2,976,017 Le Bus Mar. 21, 1961 

